How valid is Obsessive-Compulsive Inventory-Revised Scale Among Sri Lankan adults?

BACKGROUND: Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder with a lifetime prevalence of 1.9%–3.0% in the general population. It is an easily missed diagnosis. Although several paper-based tools have been developed, none are culturally validated for Sri Lankans to screen for OCD at field level. AIMS: This study aimed to translate and assess the validity and reliability of obsessive-compulsive inventory-revised scale (OCI-R) for Sri Lankan adults. SETTING AND DESIGN: This study was a case–control study. MATERIALS AND METHODS: This was conducted among 89 OCD patients and 89 controls recruited from the National Hospital of Sri Lanka to assess the criterion validity of OCI-R (an 18-item tool on common OCD symptoms using six subscales), by applying it and the gold standard (clinical diagnosis made by two independent consultant psychiatrists) to the same patient simultaneously. Before this, the tool was translated into local language (Sinhala) by bilingual experts and two psychiatrists using the forward-backward translation method. Receiver operating characteristics (ROC) curve was drawn to determine the cutoff value to identify OCD in Sri Lanka. RESULTS: The translated tool demonstrated the following: sensitivity 84.4%, specificity 85.6%, positive predictive value 85.4%, negative predictive value 84.6%, and positive and negative likelihood ratios of 5.86 and 0.18, respectively. The cutoff value for diagnosing OCD was 21 according to the ROC curve. Internal consistency (Cronbach's alpha reliability coefficient) of all six domains and the total scale showed values exceeding Nunnally's criteria of 0.7. CONCLUSIONS: Sinhala version of the OCI-R scale was identified as a valid and reliable screening instrument to be applied in Sri Lankan adults.